Using liquid or solid iodized fertilizer derived from seaweed, we cultivated a number of leafy vegetables in field trial, including spinach, Chinese cabbage, lettuce, cilantro, mustard, and snow cabbage to study the characteristics of iodine uptake and accumulation by these plants. Our results indicate that the iodine content in the edible parts of leafy vegetable increases with increasing level of exogenous iodine, and decreases after the initial application of the iodized fertilizer. Surface application of liquid iodized fertilizer is more favorable for iodine accumulation in vegetable leaves, whereas root application of solid iodized fertilizer leads to more accumulation of iodine in roots.
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